The professional group has plugged a very funny show into its season, and although it's not homemade, it is the kick-off of the national tour of "Murder for Two," by Joe Kinosian and Kellen Blair. It's a crazy quilt of vaudeville/farce/murder mystery-a-la-Agatha Christie, which delivers plenty of opportunities for the audience to get both mental and physical whiplash. Non-stop laughter and the need for parsing a constant parade of characters in a convoluted crime scene provides us with a theatrical thrill ride.

And it's all delivered by two impressively skilled actor-singers who also happen to be very capable pianists. It's this aspect that makes us sit up and take notice, and it provides an immeasurable dimension to what could be an upbeat but been-there-done that romp.

Kinosian, who plays a dozen or so characters (and sings and dances and plays the piano), is one of the creators of the show who along with friend and lyricist Blair launched the show in 2011 in Chicago. It's enjoyed a successful New York run (with different actors), but it's an absolutely perfect show for touring. And ATC has provided a nurturing launching pad.

Ian Lowe is Marcus, the wannabe detective who happens to be at the scene of the murder of Andrew Whatley, a famous novelist, who, it turns out, has produced works in which the leading characters are friends and acquaintances who have gathered for his surprise birthday party. But in a moment when the lights conveniently black out, a shot rings out, and the imaginary Whatley lies in a pool of imaginary blood. Any of the group could be a suspect, and Marcus decides he can prove his detective-worthiness in this setting.

Kinosian gives us the army of The Suspects in a non-stop energetic passion for the motley crew, distilling each to a specific physical characteristic, perhaps with the help of a prop, or maybe not. Although Lowe's participation is not as showy, the actor knows his job and does exactly what he needs to do. His singular character becomes the industrial strength glue that gives the wacky story a sturdy semblance of sense.

The show has been directed by Scott Schwartz from the get-go. He wrangles his actors and the characters they discover with a measured hand, and gives us a frenetic feeling pace rooted in the storytelling, so it never feels artificial (like maybe we need to be distracted by a weakness.)

That's why the last few moments of the presentation seem weird, and actually deflate the energy with which the audience responds. The piece reaches an obvious conclusion and we definitely feel The End, when that "amen" moment is interrupted and a huge mirror is revealed on stage and the actors sit at the piano and play a piece together. Not needed; not really sure why it happens; not appreciated.

It's easy to conclude this is not great theater. It's too light, frivolous. It doesn't have enough gravitas or intellectual heft which ultimately reveals itself, even in a comedic setting, as many plays do.

But this show is great theater in the all-too-often forgotten aspect of knowing exactly what it is and executing it pretty perfectly. And it celebrates transparently the numerous skills required to make theater a magical moment conjured by both considered invention and creativity on the fly.